Dynamic Analysis Of Planetary Transmission System On TY Wind Power Gearbox

With a high speed development of society and industrial process, sustainable development problems of environment and energy have become primary problems that existence and development of human beings face. Wind power generation is adopted preferentially by every country in the world because of following advantages, including shorter construction time, flexible installed capacity, not pollute the environment and not consume any fuel. Wind power gearbox is the most important but the most fragile component in wind turbine mechanical transmission system. And it plays the role of increasing speed and reducing torque. In addition, the design rationality of wind power gearbox affects the normal operation of fans seriously. Our country has become a country which has the most wind power installed capacities in the world. So, China is worthy of the name of the wind power country, but not a power country. With developed countries, there is a certain gap in this area of wind power equipment manufacture. The designing and manufacturing technology of wind power gearbox has been regarded as one of the main bottlenecks constraining wind power manufacturing development. And the failure rate of domestically produced wind power gearbox remains stubbornly high. Therefore, it is meaningful to strengthen design and research of wind power gearbox for improving healthy development of wind power manufacturing.This paper takes megawatt wind power gear box of TY type as research subject. To begin with, dynamics simulation analysis research is conducted. Then, the improvement methods of potential weakness are put forward based on analysis results. At last, resonance analysis of the whole wind power gear box system is carried out. The main research contents and results are shown as follows.1) Through conducting analysis of gearbox structure in detail, and by comparing with mainstream model, the main difference of TY type is in the way of load average distribution. The first stage adopts floating load average distribution of sun gear while the second stage adopts floating load average distribution of planetary carrier.2) The load applied on wind power gear box is analyzed, and treatment methods of alternating load is discussed. In addition, equivalent treatment of actual alternating load is conducted.3) Taking influence of structure system into consideration, rigid flexible coupling TY type virtual prototype of wind power gearbox is established, and realizes united simulation of Pro/E, Hypermesh and Romax Designer. Strength analysis of imported components is conducted by the finite element method. At the same time, on the basis of what has done as above, it can be easily to test whether the imported components are taking part in system transmission. 4) Considering impact loads generated by turbulence and emergency brake, steady-state analysis, which is under multiple load conditions, of transmission system in TY-1wind power gear box, is carried out. Four weakness parts are found through analysis, including two bearings in high speed and upper wind, input solar wheel and output pinion in high speed. Through analysis, it can be discovered that dynamic bearing capacity of high speed axis, which is in high speed and upper wind, is not enough, and edge load is applied to low speed axis, which is in high speed. Contact fatigue damage of fault gear is serious. Because of meshing dislocation, local stress is bigger, and load distribution of tooth surface is uneven. Therefore, fatigue pitting is easily generating on tooth surface. Besides, impact load increases fatigue damage of components, and reduces components life. For this reason, bearing on high speed axis, which is in high speed and upper wind, is changed into bearing with a high dynamic bearing capacity. And the fixed-floating supporting way of the low speed axis is changed into fixed supporting way at both ends. Bearings life meet the design requirements, and at the same time, free end deformation of low speed axis and influence of second grade gear transmission are reduced. Furthermore, through shape modification, it not only improves uneven phenomenon of tooth surface load distribution due to meshing dislocation, but also reduces gear transmission error and enhances gear transmission dynamic characteristics.5) Through resonance analysis of virtual prototype in TY wind power gear box, potential resonance response points are found. By using Romax power solution module, the first forty order nature frequency and vibration mode are solved. The resonance analysis of gear transmission system is conducted through Campbell graph, and ten potential vibration response points, which are under the function of characteristic frequency system, can be found out. Especially five, eleven, twenty-four order natural frequencies have fallen into the main operation area of wind turbine.Through analyzing the vibration mode of resonance point, twist and radial shifting of gears are caused in these resonance points.